California's $17b Water Project Wins Key Backing

David Wagman

11 October 2017

A water board representing a large swath of Southern California voted October 10 to shoulder a 25 percent cost share for a $17 billion water infrastructure project intended to modernize how water is distributed from northern parts of the state to southern.

The Metropolitan Water District’s Board of Directors voted to support a state-federal project to modernize the state water system and help improve supply reliability.

Metropolitan’s board approved the district’s 26 percent share of financing the California WaterFix project as well as move forward on a governance structure to build and finance the $17 billion project. Metropolitan’s share would be about $4.3 billion.

The Delta is a source of water for two-thirds of California's population and one-third of its irrigated farmland. The WaterFix plan seeks to accomplish three main goals:

Allow for more natural flows in the Delta to benefit salmon, smelt and other species.

Increase water supply reliability by giving the water projects that divert from the Delta more flexibility to move water without harming fish.

Guard the Delta water diversion point from natural disaster disruption, such as earthquake or flood.

Pumping Facilities

The proposal involves building three new intakes, each with a maximum diversion capacity of 3,000 cubic feet per second, on the east bank of the Sacramento River in the north Delta.

Each intake site would use on-bank fish screens. Two 40-foot-wide underground pipelines would carry the diverted water by gravity flow approximately 30 miles to the expanded Clifton Court Forebay, where two pumping plants would be constructed to maintain optimal water levels in the forebay for the existing State Water Project (SWP) and Central Valley Project (CVP) pumping facilities. Those existing pumps would lift the water into the canals that flow hundreds of miles to supply San Joaquin Valley farms and cities as far away as San Diego.

The north Delta intakes would be operated with the existing south Delta pumping facilities as a “dual conveyance system,” which would be a significant upgrade from the existing system, project developers say. The existing south Delta pumps pull water from nearby channels in an unnatural direction, called "reverse flows," which can draw fish off their migratory path into predator-rich channels.

Vulnerable to Floods

Besides the environmental imperative to restore more natural flows to the Delta, there are infrastructure security reasons to modernize the Delta water conveyance system. The Delta's peat soil, composed of wetland plants, oxidizes when dried and tilled.

Many of the approximately 60 islands that make up the Delta have sunk as much as 20 feet below sea level in their centers. Engineers worry that should an earthquake, flood or some other force knock down the levees, the sunken islands would fill up with water, drawing saltwater from San Francisco Bay eastward toward the SWP and CVP south Delta water intakes. Water supplies could be disrupted depending upon the extent of the damage.

“Given our size, Metropolitan is the anchor tenant for any successful California WaterFix, and this vote puts us on record as being ready and willing to participate. We still have a ways to go before we have a final, fully funded project, but this vote keeps WaterFix on the path to finding a viable and lasting solution,” says Metropolitan General Manager Jeffrey Kightlinger.

The board vote follows more than a decade of planning, preliminary design, environmental analysis, regulatory review and public input. It also concludes several months of public review by Metropolitan’s board, including discussions in July and August on a series of policy white papers examining the project’s construction, operations, benefits and cost.

Among State Water Contractors, the boards of Zone 7 Water Agency, Mojave Water Agency, San Gorgonio Pass Water Agency, Desert Water Agency, San Bernardino Municipal Water District and Crestline-Lake Arrowhead Water Agency have all voted to support the project.

Kern County Water Agency’s board is scheduled to vote on California WaterFix October 12, with other agencies scheduled to follow.

A 3-D METHOD FOR GAUGING FLOOD IMPACT

According to the NOAA National Severe Storms Laboratory, flooding causes more damage than any other severe weather-related event, an average of $5 billion per year in the U.S. It kills more people each year than tornadoes, hurricanes or lightning, and it occurs in every U.S. state and territory. It’s a threat experienced worldwide, anywhere that receives rain.

A flood event in Iowa back in 2008 cost $10 billion in damages to the state, prompting the establishment of the Iowa Flood Center (IFC) at the University of Iowa, the first center in the country for advanced flood-related research and education.

Simplified 2-D models are the current state-of-the-art for predicting flood wave propagation, but an IFC team led by UI professor George Constantinescu is creating 3-D non-hydrostatic flood models to more accurately simulate how floods spread across land. These 3-D models can also be used to assess and improve the predictive capabilities of the 2-D models already in use.

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